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1.
Psychol Med ; 52(12): 2263-2269, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-33183361

RESUMO

BACKGROUND: Increasing numbers of children with perinatally acquired HIV (PaHIV) are transitioning into adult care. People living with behaviourally acquired HIV are known to be at more risk of psychosis than uninfected peers. Young adults living with PaHIV face numerous risk factors; biological: lifelong exposure to a neurotrophic virus, antiretroviral medication and immune dysfunction during brain development, and environmental; social deprivation, ethnicity-related discrimination, and migration-related issues. To date, there is little published data on the prevalence of psychotic illness in young people growing up with PaHIV. METHODS: We conducted a retrospective case note review of all individuals with PaHIV aged over 18 years registered for follow up at a dedicated clinic in the UK (n = 184). RESULTS: In total, 12/184 (6.5%), median age 23 years (interquartile range 21-26), had experienced at least one psychotic episode. The presentation and course of the psychotic episodes experienced by our cohort varied from short-lived symptoms to long term illness and nine (75%) appear to have developed a severe and enduring mental illness requiring long term care. CONCLUSION: The prevalence of psychosis in our cohort was clearly above the lifetime prevalence of psychosis in UK individuals aged 16-34 years, which has been reported to be 0.5-1.0%. This highlights the importance of clinical vigilance regarding the mental health of young people growing up with PaHIV and the need to integrate direct access to mental health services within the HIV centres providing medical care.


Assuntos
Infecções por HIV , Transtornos Psicóticos , Adolescente , Adulto , Criança , Infecções por HIV/epidemiologia , Humanos , Saúde Mental , Pessoa de Meia-Idade , Transtornos Psicóticos/epidemiologia , Estudos Retrospectivos , Reino Unido/epidemiologia , Adulto Jovem
2.
Mol Reprod Dev ; 79(4): 255-61, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22231935

RESUMO

Germline stem cells (GSCs) can be used for large animal transgenesis, in which GSCs that are genetically manipulated in vitro are transplanted into a recipient testis to generate donor-derived transgenic sperm. The objectives of this study were to explore a non-viral approach for transgene delivery into goat GSCs and to investigate the efficiency of nucleofection in producing transgenic sperm. Four recipient goats received fractionated irradiation at 8 weeks of age to deplete endogenous GSCs. Germ cell transplantations were performed 8-9 weeks post-irradiation. Donor cells were collected from testes of 9-week-old goats, enriched for GSCs by Staput velocity sedimentation, and transfected by nucleofection with a transgene construct harboring the human growth hormone gene under the control of the goat beta-casein promoter (GBC) and a chicken beta-globin insulator (CBGI) sequence upstream of the promoter. For each recipient, transfected cells from 10 nucleofection reactions were pooled, mixed with non-transfected cells to a total of 1.5 × 10(8) cells in 3 ml, and transplanted into one testis (n = 4 recipients) by ultrasound-guided cannulation of the rete testis. The second testis of each recipient was removed. Semen was collected, starting at 9 months after transplantation, for a period of over a year (a total of 62 ejaculates from four recipients). Nested genomic PCR for hGH and CBGI sequences demonstrated that 31.3% ± 12.6% of ejaculates were positive for both hGH and CBGI. This study provides proof-of-concept that non-viral transfection (nucleofection) of primary goat germ cells followed by germ cell transplantation results in transgene transmission to sperm in recipient goats.


Assuntos
Animais Geneticamente Modificados/genética , Células Germinativas/transplante , Espermatozoides/fisiologia , Transplante de Células-Tronco/métodos , Transfecção/métodos , Transgenes , Animais , Caseínas/genética , Galinhas , Feminino , Genótipo , Células Germinativas/citologia , Cabras , Hormônio do Crescimento Humano/genética , Hormônio do Crescimento Humano/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Regiões Promotoras Genéticas , Espermatozoides/citologia , Células-Tronco/citologia , Testículo/fisiologia , Globinas beta/genética
3.
BJOG ; 119(11): 1293-301, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22882742

RESUMO

BACKGROUND: The colposcopy-directed punch biopsy is widely used in the management of women with abnormal cervical cytology; however, its accuracy compared with definitive histology from an excision biopsy is not well established. OBJECTIVES: To assess the accuracy of the colposcopy-directed punch biopsy to diagnose high-grade cervical intraepithelial neoplasia (CIN) by performing a systematic review and meta-analysis. SEARCH STRATEGY: A systematic search of MEDLINE, EMBASE and the Cochrane Library was performed. SELECTION CRITERIA: Articles that compared the colposcopically directed cervical punch biopsy with definitive histology from an excisional cervical biopsy or hysterectomy. DATA COLLECTION AND ANALYSIS: Random effects and hierarchical summary receiver operating characteristic regression models were used to compute the pooled sensitivity and specificity applying different test cut-offs for outcomes of high-grade CIN. MAIN RESULTS: Thirty-two papers comprising 7873 paired punch/definitive histology results were identified. The pooled sensitivity for a punch biopsy defined as test cut-off CIN1+ to diagnose CIN2+ disease was 91.3% (95% CI 85.3-94.9%) and the specificity was 24.6% (95% CI 16.0-35.9%). In most of the studies, the majority of enrolled women had positive punch biopsies. Pooling of the four studies where the excision biopsy was performed immediately after the punch biopsy, and where the rate of positive punch biopsies was considerably lower, yielded a sensitivity of 81.4% and specificity of 63.3%. AUTHOR'S CONCLUSION: The observed high sensitivity of the punch biopsy derived from all studies is probably the result of verification bias.


Assuntos
Biópsia/métodos , Colo do Útero/patologia , Colposcopia , Displasia do Colo do Útero/patologia , Colposcopia/métodos , Feminino , Humanos , Histerectomia , Sensibilidade e Especificidade
5.
J Clin Invest ; 65(2): 338-46, 1980 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7356683

RESUMO

Plasma 1-norepinephrine and epinephrine contents were strikingly elevated in 70 patients during evolution of myocardial infarction. Propranolol or placebo, 0.1 mg/kg i.v., was administered randomly an average of 10 h after infarction and continued orally for 3 d. Propranolol, but not placebo, acutely decreased 1-norepinephrine contents from 2.24 +/- 1.33 (mean +/- SD) to 1.31 +/- 0.74 microgram/liter, P less than 0.001, and epinephrine contents from 0.97 +/- 0.42 to 0.74 +/- 0.42 microgram/liter, P less than 0.02. Decreases in 1-norepinephrine contents were related to the initial plasma concentrations, r = 0.85, P less than 0.001. A similar, but less strong relationship was observed between the initial epinephrine contents and propranolol-induced changes, r = -0.51, P less than 0.01. Propranolol reduced plasma-free fatty acid contents from 1,121 +/- 315 to 943 +/- 274 mumol/liter, P less than 0.001. Decreases in plasma contents of free fatty acids were related to decreases in epinephrine, r = 0.66, P less than 0.001. Propranolol did not cause significant additional changes in plasma catecholamine contents during the subsequent 3 d. In the placebo group 1-norepinephrine contents had decreased 24 h after infarction from 1.92 +/- 0.99 to 1.37 +/- 0.93 microgram/liter, P less than 0.02. Plasma epinephrine contents did not change. Heart rate remained below the control values during the entire study period in the propranolol, but increased in the placebo group. The data indicate that sympathetic hyperactivity, indirectly reflected by plasma catecholamine contents, is acutely reduced by propranolol during evolution of myocardial infarction.


Assuntos
Catecolaminas/sangue , Infarto do Miocárdio/tratamento farmacológico , Propranolol/farmacologia , Sistema Nervoso Simpático/efeitos dos fármacos , Adulto , Idoso , Epinefrina/sangue , Ácidos Graxos não Esterificados/sangue , Feminino , Hemodinâmica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/fisiopatologia , Norepinefrina/sangue , Sistema Nervoso Simpático/fisiopatologia
6.
J Clin Invest ; 46(10): 1625-42, 1967 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6061740

RESUMO

Airway pressure was continuously recorded in an isolated horizontally mounted canine heart-lung preparation during abrupt, stepwise 100-200 ml inflations to 20-25 cm water pressure, and subsequent deflations. With each change in volume there was a steep rise or fall in pressure, followed by stress relaxation to a static equilibrium airway pressure. Comparison was made between the nonperfused state and during perfusion with whole blood at 100 ml/kg dog wt per min, and left atrial pressure of 10 mm Hg. Pressure tracings were similar during deflation in the perfused and the nonperfused lung. During inflation, in the middle range of lung inflation volumes, the peak inflation and equilibrium airway pressures were greater in the nonperfused state; maximum difference of static pressures in nine preparations averaged 146% of perfused values and the average stress relaxation difference from eight of these was 276%. Lung distensibility was the same with packed red cells or plasma perfusates and was not changed by varying the perfusion rate up to 220 ml/kg per min. During cyclic ventilation, dynamic compliance was similarly greater in the perfused than in the nonperfused state in the middle range of inflation volumes. Static distention of the vascular bed produced similar results with progressive improvement in distensibility in mid-inflation range up to a hydrostatic pressure of 15 cm blood. These data suggest that the distended pulmonary vascular bed provides structural airway support which facilitates entry of gas into the terminal respiratory units at diminished pressure.


Assuntos
Pressão Sanguínea/fisiologia , Pulmão/fisiologia , Animais , Velocidade do Fluxo Sanguíneo , Cães , Pulmão/irrigação sanguínea , Perfusão , Pletismografia , Pressão
7.
J Clin Invest ; 49(10): 1885-902, 1970 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-5460498

RESUMO

Hemodynamics and myocardial metabolism were evaluated in 18 patients in cardiogenic shock following acute myocardial infarction. The response to l-norepinephrine was studied in seven cases and the response to isoproterenol in four cases. Cardiac index (CI) was markedly reduced, averaging 1.35 liters/min per m(2). Mean arterial pressure ranged from 40 to 65 mm Hg while systemic vascular resistance varied widely, averaging 1575 dyne-sec-cm(-5). Coronary blood flow (CBF) was decreased in all but three patients (range 60-95, mean 71 ml/100 g per min). Myocardial oxygen consumption (MV(O2)) was normal or increased ranging from 5.96 to 11.37 ml/100 g per min. Myocardial oxygen extraction was above 70% and coronary sinus oxygen tension was below 22 mm Hg in most of the patients. The detection of the abnormal oxygen pattern in spite of sampling of mixed coronary venous blood indicates the severity of myocardial hypoxia. In 15 studies myocardial lactate production was demonstrated; in the remaining three lactate extraction was below 10%. Excess lactate was present in 12 patients. During l-norepinephrine infusion CI increased insignificantly. Increased arterial pressure was associated in all patients by increases in CBF, averaging 28% (P < 0.01). Myocardial metabolism improved. Increases in MV(O2) mainly paralled increases in CBF. Myocardial lactate production shifted to extraction in three patients and extraction improved in three. During isoproterenol infusion CI increased uniformly, averaging 61%. Mean arterial pressure remained unchanged but diastolic arterial pressure fell. CBF increased in three patients, secondary to decrease in CVR. Myocardial lactate metabolism deteriorated uniformly; lactate production increased or extraction shifted to production. In the acute state of coronary shock the primary therapeutic concern should be directed towards the myocardium and not towards peripheral circulation. Since forward and collateral flow through the severely diseased coronary bed depends mainly on perfusion pressure, l-norepinephrine appears to be superior to isoproterenol; phase-shift balloon pumping may be considered early when pharmacologic therapy is unsuccessful.


Assuntos
Vasos Coronários/fisiopatologia , Hemodinâmica , Isoproterenol/uso terapêutico , Infarto do Miocárdio/complicações , Miocárdio/metabolismo , Norepinefrina/uso terapêutico , Choque/etiologia , Idoso , Artérias , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea , Feminino , Coração/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Humanos , Isoproterenol/farmacologia , Lactatos/metabolismo , Masculino , Pessoa de Meia-Idade , Norepinefrina/farmacologia , Oxigênio/sangue , Consumo de Oxigênio , Pressão Parcial , Choque/tratamento farmacológico , Choque/fisiopatologia , Resistência Vascular
8.
J Clin Invest ; 50(9): 1885-900, 1971 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-5564396

RESUMO

The effect of intra-aortic counterpulsation (IACP, 22-94 hr) on hemodynamics and cardiac energetics was evaluated in 10 patients in shock after acute myocardial infarction. The data clearly indicate that IACP improves myocardial oxygenation, enhances peripheral perfusion, and probably improves myocardial contractility in the severely diseased heart. Before treatment, decreases in cardiac index (mean value, 1.22 liter/min per m(2)), systolic ejection rate (67 ml/sec), and time-tension index per minute (1280 mm Hg.sec/min) were observed. Systemic vascular resistance varied widely. Low coronary blood flow (68 ml/min per 100 g) was associated with increased myocardial oxygen extraction (79%), low coronary sinus oxygen tension (20 mm Hg), and abnormal myocardial lactate-pyruvate metabolism. During 4-6 hr of IACP, systolic pressure and left ventricular outflow resistance decreased by 18% and 24%, respectively, while cardiac index improved by 38%. Diastolic arterial pressure rose 98%. Increase in coronary blood flow from an average of 68 to 91 ml/100 g per min (P < 0.001) was significantly correlated with rise in mean arterial pressure (r = 0.685). This correlation was best expressed in a third-order curve, which intercepts the point of no flow at a mean aortic pressure of 30 mm Hg. The flow-pressure curve is relatively flat above 65-70 mm Hg, but becomes steeper as mean aortic pressure falls below this point. Myocardial oxygen consumption remained essentially unchanged during early IACP and tended to rise during the later stages. However, the relationship of cardiac work performed to oxygen availability was markedly improved. Myocardial lactate production of 6% shifted to 15% extraction (P < 0.001). After termination of IACP, hemodynamics and myocardial perfusion and metabolism remained improved in the four patients who could be reevaluated. Although the acute shock state was reversed in all patients, only one left the hospital. Extensive myocardial damage limits the long-term survival of such patients. Therefore early IACP seems desirable, when subtle evidence of pump failure after acute myocardial infarction occurs. Early use of IACP may prevent the development of severe coronary shock or may stabilize cardiac energetics in severe shock facilitating subsequent surgical intervention.


Assuntos
Circulação Assistida , Coração/fisiopatologia , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/cirurgia , Choque/fisiopatologia , Idoso , Análise de Variância , Aorta , Pressão Sanguínea , Computadores , Feminino , Humanos , Lactatos/metabolismo , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Consumo de Oxigênio , Piruvatos/metabolismo , Choque/metabolismo
9.
J Clin Invest ; 104(9): R33-9, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10545530

RESUMO

The transcription factor insulin promoter factor-1 (IPF-1) plays a central role in both the development of the pancreas and the regulation of insulin gene expression in the mature pancreatic beta cell. A dominant-negative frameshift mutation in the IPF-l gene was identified in a single family and shown to cause pancreatic agenesis when homozygous and maturity-onset diabetes of the young (MODY) when heterozygous. We studied the role of IPF-1 in Caucasian diabetic and nondiabetic subjects from the United Kingdom. Three novel IPF-1 missense mutations (C18R, D76N, and R197H) were identified in patients with type 2 diabetes. Functional analyses of these mutations demonstrated decreased binding activity to the human insulin gene promoter and reduced activation of the insulin gene in response to hyperglycemia in the human beta-cell line Nes2y. These mutations are present in 1% of the population and predisposed the subject to type 2 diabetes with a relative risk of 3.0. They were not highly penetrant MODY mutations, as there were nondiabetic mutation carriers 25-53 years of age. We conclude that mutations in the IPF-1 gene may predispose to type 2 diabetes and are a rare cause of MODY and pancreatic agenesis, with the phenotype depending upon the severity of the mutation.


Assuntos
Diabetes Mellitus Tipo 2/genética , Proteínas de Homeodomínio , Transativadores/genética , Adulto , Idoso , Western Blotting , Núcleo Celular/metabolismo , Células Cultivadas , Citoplasma/metabolismo , Análise Mutacional de DNA , Feminino , Predisposição Genética para Doença , Glucose/metabolismo , Humanos , Insulina/genética , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Linhagem , Fenótipo , Fosforilação , Transcrição Gênica
10.
Nat Biotechnol ; 17(5): 456-61, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10331804

RESUMO

In this study, we demonstrate the production of transgenic goats by nuclear transfer of fetal somatic cells. Donor karyoplasts were obtained from a primary fetal somatic cell line derived from a 40-day transgenic female fetus produced by artificial insemination of a nontransgenic adult female with semen from a transgenic male. Live offspring were produced with two nuclear transfer procedures. In one protocol, oocytes at the arrested metaphase II stage were enucleated, electrofused with donor somatic cells, and simultaneously activated. In the second protocol, activated in vivo oocytes were enucleated at the telophase II stage, electrofused with donor somatic cells, and simultaneously activated a second time to induce genome reactivation. Three healthy identical female offspring were born. Genotypic analyses confirmed that all cloned offspring were derived from the donor cell line. Analysis of the milk of one of the transgenic cloned animals showed high-level production of human antithrombin III, similar to the parental transgenic line.


Assuntos
Clonagem de Organismos , Cabras/genética , Técnicas de Transferência Nuclear , Animais , Animais Geneticamente Modificados , Antitrombina III/genética , Southern Blotting , Núcleo Celular/fisiologia , Desenvolvimento Embrionário e Fetal , Feminino , Cabras/fisiologia , Humanos , Hibridização in Situ Fluorescente , Masculino , Leite/metabolismo , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição , Gravidez , Proteínas Recombinantes/metabolismo , Reprodução
11.
Diabetes ; 48(12): 2475-9, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10580439

RESUMO

The transmission disequilibrium test with use of trios (an affected proband with both parents) is a robust method for assessing the role of gene variants in disease that avoids the problem of population stratification that may confound conventional case/control studies and allows the detection of parent-of-origin effects. Trios have played a major role in defining genes in a number of polygenic conditions, including type 1 diabetes. We assessed the prevalence, clinical characteristics, and suitability for defining type 2 susceptibility genes of European type 2 diabetes trios. In a Caucasian population in the U.K., only 2.5% of type 2 patients had both parents alive. Using a nationwide strategy, we collected 182 trios defined by strict clinical criteria. Immunological and genetic testing resulted in the exclusion of 25 trios as a result of latent autoimmune diabetes (n = 13), inconsistent family relationships (n = 7), and maternally inherited diabetes and deafness (n = 5). The 157 remaining probands had similar treatment requirements to familial type 2 diabetic subjects but presented at a younger age, were more obese, and more frequently had affected parents. Using this resource, we have not found any evidence for linkage disequilibrium between type 2 diabetes and the glucokinase gene markers GCK1 and GCK2 and the chromosome 20 marker D20S197. We conclude that European type 2 diabetes trios are difficult to collect but provide an important additional approach to dissecting the genetics of type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença/genética , Núcleo Familiar , População Branca/genética , Adulto , Autoanticorpos/sangue , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/imunologia , Europa (Continente) , Feminino , Genes Dominantes , Genes Recessivos , Glutamato Descarboxilase/imunologia , Humanos , Desequilíbrio de Ligação , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Prevalência , Risco , Reino Unido
12.
Cloning Stem Cells ; 7(2): 107-18, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15971984

RESUMO

Nuclear transfer (NT) using transfected primary cells is an efficient approach for the generation of transgenic goats. However, reprogramming abnormalities associated with this process might result in compromised animals. We examined the health, reproductive performance, and milk production of four transgenic does derived from somatic cell NT. Goats were derived from two fetal cell lines, each transfected with a transgene expressing a different version of the MSP-1(42) malaria antigen, either glycosylated or non-glycosylated. Two female kids were produced per cell line. Health and growth of these NT animals were monitored and compared with four age-matched control does. There were no differences in birth and weaning weights between NT and control animals. The NT does were bred and produced a total of nine kids. The control does delivered five kids. The NT does expressing the glycosylated antigen lactated only briefly, probably as a result of over-expression of the MSP-1(42) protein. However, NT does expressing the non-glycosylated antigen had normal milk yields and produced the recombinant protein. These data demonstrated that the production of healthy transgenic founder goats by somatic cell NT is readily achievable and that these animals can be used successfully for the production of a candidate Malaria vaccine.


Assuntos
Clonagem de Organismos , Cabras/fisiologia , Proteína 1 de Superfície de Merozoito/genética , Técnicas de Transferência Nuclear , Reprodução , Animais , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/fisiologia , Comportamento Animal , Estro , Glicosilação , Cabras/genética , Leite , Plasmodium/imunologia
13.
Am J Cardiol ; 50(6): 1223-8, 1982 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7148695

RESUMO

An increase in cardiac sympathetic activity can enhance coronary vasomotor tone and lower the ventricular fibrillation threshold. We compared the transcardiac l-norepinephrine responses during cold pressor test of 20 patients with normal coronary arteries with those of 23 patients with obstructive coronary artery disease. Baseline hemodynamic data did not differ in the 2 patient groups except for left ventricular end-diastolic pressures; mean values (+/- standard deviation [SD] were 10 +/- 3.7 and 15 +/- 4.5 mm Hg in patients with normal and abnormal coronary arteries (p less than 0.01). Baseline l-norepinephrine contents averaged 295 +/- 152 (normal coronary arteries) and 250 +/- 134 pg/ml (coronary artery disease) in the arterial blood, and 273 +/- 152 and 250 +/- 115 pg/ml, respectively, in the coronary sinus blood. Hemodynamic responses during cold stimulus were similar in both groups. Also, cold pressor-induced increases in arterial and coronary sinus l-norepinephrine contents were balanced in patients with normal coronary arteries, averaging 19 +/- 30 and 17 +/- 37%, respectively. In patients with coronary artery disease, however, a 26 +/- 58% increase in arterial l-norepinephrine contents was associated with a 58 +/- 62% increase in coronary sinus l-norepinephrine contents (p less than 0.02), suggesting myocardial l-norepinephrine net release. It is concluded that transcardiac l-norepinephrine responses during cold stimulus are enhanced in patients with obstructive coronary artery disease. This response to a relatively mild sympathetic stress, reproducible by a variety of analogous stressful situations during daily life, could present an increased risk for acute cardiac events.


Assuntos
Temperatura Baixa , Doença das Coronárias/metabolismo , Miocárdio/metabolismo , Norepinefrina/metabolismo , Adulto , Idoso , Epinefrina/sangue , Feminino , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Norepinefrina/sangue , Oxigênio/sangue , Pressão Parcial
14.
Environ Health Perspect ; 62: 329-35, 1985 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3910419

RESUMO

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) has suddenly become the focal point of controversy over the relationship of chemical waste to human health. Specific concern exists regarding its potential association with human malignancy. Subcellular, cellular, and whole-animal experiments suggest that TCDD exerts much of its activity by inducing enzymes that protect the intact organism from the assault of environmental contamination. TCDD is a potent inducer of aryl hydrocarbon hydroxylase, although wide variations between species do exist. Conventional tests for mutagenicity have produced conflicting results. Animal experiments have shown the development of tumors following chronic low level ingestion of TCDD. The human evidence regarding the potential carcinogenicity of TCDD comes from occupational, military and environmental exposures. Several studies have come out of Sweden suggesting an association between sarcoma and exposure to herbicides. Although there is little solid evidence that 2,3,7,8-TCDD produces substantial chronic disability or premature death in man, a significant body of experimental evidence for its carcinogenicity makes it likely that a small number of human malignancies may be due to its action. Since 2,3,7,8-TCDD is an unwanted contaminant it could be eliminated with little measurable consequence.


Assuntos
Carcinógenos , Dioxinas/efeitos adversos , Neoplasias/induzido quimicamente , Dibenzodioxinas Policloradas/efeitos adversos , Animais , Exposição Ambiental , Escherichia coli/efeitos dos fármacos , Humanos , Camundongos , Medicina Militar , Testes de Mutagenicidade , Mutação , Neoplasias/mortalidade , Neoplasias Experimentais/patologia , Dibenzodioxinas Policloradas/farmacologia , Ratos , Salmonella typhimurium/efeitos dos fármacos , Sarcoma/induzido quimicamente , Neoplasias de Tecidos Moles/induzido quimicamente , Suécia , Estados Unidos , Vietnã
15.
Metabolism ; 45(4): 411-4, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8609824

RESUMO

The effect of the estrogen metabolites, 4-hydroxyestrone and 17alpha-dihydroequilin (metabolites of estradiol-17beta and equilin, respectively), were examined for antioxidant effects on plasma and lipoprotein lipid peroxidation . Lipid peroxidation was evaluated by products of both fatty acid (thiobarbituric acid-reactive substances [TBARS]) and cholesterol (oxysterols) oxidation from lipoproteins or whole plasma. Although all estrogens significantly reduced lipid peroxidation, 4-hydroxyestrone was far more potent than either equilin or 17alpha-dihydroequilin in inhibiting TBARS formation in lipoproteins induced by Cu2+. Similar effects were also noted on TBARS formation in THP-l macrophages in culture. However, 17alpha-dihydroequilin (along with equilin) strongly inhibited oxysterol formation, whereas 4-hydroxyestrone was ineffective. These studies suggest that different estrogens might act preferentially on distinct lipid substrates in exhibiting antioxidant effects.


Assuntos
Antioxidantes/farmacologia , Equilina/análogos & derivados , Hidroxiestronas/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Linhagem Celular , Colesterol/metabolismo , Equilina/metabolismo , Equilina/farmacologia , Ácidos Graxos/metabolismo , Humanos , Hidroxiestronas/metabolismo , Peroxidação de Lipídeos/fisiologia , Lipoproteínas LDL/metabolismo , Lipoproteínas VLDL/metabolismo , Macrófagos/citologia , Macrófagos/metabolismo , Esteróis/sangue , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
16.
Am J Prev Med ; 2(2): 103-8, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-2968809

RESUMO

The clinical recognition of dioxin-associated illness can be extremely difficult for the physician. After analyzing the relative sensitivity and specificity of reported manifestations of exposure to 2,3,7,8 tetrachlorodibenzo-p-dioxin (TCDD), we suggest criteria for the diagnosis of dioxin toxicity. Exposure to higher doses of 2,3,7,8-TCDD may lead to the appearance of chloracne and the increased excretion of porphyrins and porphyria cutanea tarda. Liver function abnormalities, peripheral neuropathy, hyperlipidemia, and evidence of weakness and depression may occur following exposure; however, these findings are less specific since diseases such as diabetes or alcoholism could cause several of these problems. The long-term effects of exposure to low-dose TCDD are currently uncertain.


Assuntos
Dioxinas/efeitos adversos , Doenças Profissionais/diagnóstico , Dibenzodioxinas Policloradas/efeitos adversos , Acidentes de Trabalho , Acne Vulgar/induzido quimicamente , Acne Vulgar/diagnóstico , Doença Hepática Induzida por Substâncias e Drogas , Humanos , Hepatopatias/diagnóstico , Doenças Profissionais/induzido quimicamente , Porfirias/induzido quimicamente , Porfirias/diagnóstico , Dermatopatias/induzido quimicamente , Dermatopatias/diagnóstico
17.
Head Neck Surg ; 7(4): 272-85, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3988532

RESUMO

The multiple punch technique of hair transplantation, utilizing the principle of donor dominance, has proven to be a cosmetically acceptable procedure in properly selected patients in the presenter's 24-year experience. Careful planning with attention to aesthetic principles, especially in frontal hairline placement, in donor site selection and with regard to the ratio between the donor supply and the existing or potential future extent of baldness, together with meticulous surgical technique, are essential for satisfactory results. Scalp reduction, in which bald areas of crown and midscalp are serially excised, with extensive subgaleal undermining is a highly useful adjunct to grafting in many patients with moderately extensive male pattern baldness who have adequate scalp mobility by enabling the available donor supply to be concentrated and thus provide more effective coverage in the frontal scalp.


Assuntos
Alopecia/cirurgia , Estética , Cabelo/transplante , Couro Cabeludo/cirurgia , Adulto , Feminino , Humanos , Masculino , Métodos , Pessoa de Meia-Idade , Complicações Pós-Operatórias
18.
Fertil Steril ; 69(1): 73-7, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9457937

RESUMO

OBJECTIVE: To determine plasma lipid peroxidation parameters in eumenorrheic and amenorrheic athletes and to evaluate differences in their response to exercise-induced oxidative stress. In female athletes, intense physical exercise has been shown to be associated with an increased occurrence of menstrual dysfunction with lower levels of E2. Recently, a protective role has been demonstrated for estrogens as free radical scavengers. DESIGN: Comparison of eumenorrheic and amenorrheic athletes before and after an acute bout of exercise. SETTING: Academic Research Environment. PATIENT(S): Seven eumenorrheic (normally menstruating) and seven amenorrheic (<3 menses/year) female athletes aged 18 to 35 years participating in regular training. MAIN OUTCOME MEASURE(S): Plasma and low-density lipoprotein oxidation parameters, plasma E2 and vitamin E levels, and creatine kinase activity. RESULT(S): Both the amenorrheic and eumenorrheic athletes demonstrated a significant decrease in the lag time of conjugated diene formation after exercise (P < 0.01), with greater magnitude of change occurring in the amenorrheic athletes (P < 0.05). In addition, postexercise samples from amenorrheic (but not eumenorrhic) athletes showed a significant (P < 0.01) increase in oxysterol formation as compared to baseline values. Amenorrheic athletes also demonstrated a significantly higher baseline creatine kinase activity and a nonsignificant (P = 0.04) trend of an increase in creatine kinase activity after exercise. CONCLUSION(S): The results of this study shows that amenorrheic female athletes demonstrate an increased potential for lipid peroxidation after exercise. This could be related to lower plasma E2 levels in this group, considering the strong free radical scavenging ability of estrogens identified recently.


Assuntos
Amenorreia/metabolismo , Exercício Físico , Peróxidos Lipídicos/metabolismo , Esportes , Adolescente , Adulto , Amenorreia/sangue , Creatina Quinase/sangue , Estradiol/sangue , Feminino , Humanos , Valores de Referência
19.
Brain Res Bull ; 51(1): 63-8, 2000 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-10654582

RESUMO

Regional distribution of gonadotropin-releasing hormone (GnRH)-like-, beta-endorphin (beta-end)-like-, and methionine-enkephalin (met-enk)-like-immunoreactivity was quantified across various regions of the central nervous system (CNS) of male and female goats by using highly specific radioimmunoassays. All the animals were sacrificed during the months of March through June (non-breeding season). Although the distribution of these three neuropeptides was similar to other mammalian species, species-specific gender differences in the levels of neuropeptides were noticed in the goat CNS. Highest levels of GnRH-like immunoreactivities were found in the hypothalamus. The hypothalamus of male goats exhibited significantly higher levels of GnRH-like immunoreactivities compared to female goats. Other regions exhibiting GnRH-like immunoreactivities included olfactory bulbs, preoptic and supraoptic regions, and mamillary bodies. Both beta-end- and met-enk immunoreactivities were detected in all selected regions of goat CNS, but highest levels of these opioid peptide-like immunoreactivities were limited to the forebrain regions of the goat. The supraoptic area of the female goats contained significantly higher levels of beta-end-like immunoreactivities than that of the male goats. Met-enk-peptide-like immunoreactivity also exhibited gender-specific differences in its content in some regions of the CNS. The male goats exhibited significantly higher levels of met-enk-like immunoreactivity in both the striatal and hypothalamic regions of the brain.


Assuntos
Química Encefálica , Encefalina Metionina/análise , Hormônio Liberador de Gonadotropina/análise , Medula Espinal/química , beta-Endorfina/análise , Análise de Variância , Animais , Córtex Cerebral/química , Feminino , Cabras , Hipotálamo/química , Masculino , Bulbo/química , Bulbo Olfatório/química , Área Pré-Óptica/química , Radioimunoensaio
20.
Crit Care Clin ; 1(3): 435-51, 1985 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3916788

RESUMO

The function of the human heart relies on the complex interplay of preload, afterload, and contractility. Alterations of all three variables occur in disease states. New developments in monitoring allow assessment of cardiac function at the bedside and contribute to patient care.


Assuntos
Cuidados Críticos , Cardiopatias/fisiopatologia , Coração/fisiologia , Trifosfato de Adenosina/fisiologia , Débito Cardíaco , Ventrículos do Coração/fisiopatologia , Humanos , Contração Miocárdica , Miofibrilas/fisiologia , Volume Sistólico
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